| A | B |
|---|
| universe | large expanse of space |
| sun spots | cooler places on the Sun |
| gravity | a pull that keeps the Sun in orbit |
| rotate | spin |
| revolve | travels around another object |
| atmosphere | layer if air |
| axis | imaginary line from pole to pole |
| equator | imaginary center line around a planet |
| satellite | small body revolving around a planet |
| craters | bowl-shaped holes created by impacts |
| polar ice caps | frozen areas found at the poles |
| meteor | stone or metal traveling through space |
| meteorite | stone or metal that travels through our atmosphere |
| constellations | groups of stars |
| Polaris | North Star |
| solar system | nine planets, their moons and the Sun |
| Pluto | the ninth planet |
| Mercury | the first planet |
| Earth | third planet from the Sun |
| Voyager | a space probe |
